EVPN Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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EVPN Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

VRF leaking for EVPN E-LAN

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Introduces VRF leaking capabilities for EVPN E-LAN, describes features of Layer 2 interconnection using VRF leaking, and provides configuration procedures to enable optimal traffic distribution across virtual routing instances.


A virtual routing and forwarding (VRF) instance is a network virtualization technology that

  • provides logical separation of network resources by creating multiple isolated virtual networks

  • operates independently with its own routing table, forwarding behavior, and network policies, and

  • enables communication among devices within the same VRF while isolating them from devices in other VRFs.

Table 1. Feature History Table

Feature Name

Release Information

Feature Description

VRF Leaking for EVPN Single-Homing

Release 26.3.1

Introduced in this release on: Modular Systems (8800 [LC ASIC: K100])(select variants only*)

*This feature is supported on:

  • 88-LC1-48Y8H-EM

  • 88-LC1-16H16F-EM

VRF Leaking for EVPN Single-Homing

Release 26.1.1

Introduced in this release on: Centralized Systems (8400 [ASIC: K100])(select variants only*)

*This feature is now supported on Cisco 8404-SYS-D routers.

VRF Leaking for EVPN Single-Homing

Release 25.4.1

Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only*)

*This feature is now supported on:

  • 8011-32Y8L2H2FH

  • 8011-12G12X4Y-A

  • 8011-12G12X4Y-D

VRF Leaking for EVPN Single-Homing

Release 25.1.1

Introduced in this release on: Fixed Systems (8010 [ASIC: A100]) (select variants only*)

*This feature is now supported on the Cisco 8011-4G24Y4H-I routers.

VRF Leaking for EVPN Single-Homing

Release 24.4.1

Introduced in this release on: Fixed Systems (8700) (select variants only*)

*The VRF leaking functionality is now extended to the Cisco 8712-MOD-M routers.

VRF Leaking for EVPN Single-Homing

Release 24.3.1

Introduced in this release on: Fixed Systems (8200, 8700); Modular Systems (8800 [LC ASIC: P100]) (select variants only*)

*The VRF leaking functionality is now extended to:

  • 8212-48FH-M

  • 8711-32FH-M

  • 88-LC1-52Y8H-EM

  • 88-LC1-12TH24FH-E

VRF Leaking for EVPN Single-Homing

Release 24.2.11

Introduced in this release on: Modular Systems (8800 [LC ASIC: P100]) (select variants only*)

*The VRF leaking functionality is now extended to routers with the 88-LC1-36EH line cards.

VRF Leaking for EVPN Single-Homing

Release 7.11.1

We now allow for seamless intercommunication between different VRF instances in an EVPN domain, thus enabling controlled inter-VRF communication and resource-sharing, which is helpful in multi-tenancy environments, data center deployments, and hybrid cloud scenarios.

This feature is supported only on Q200-based line cards.


Features of Layer 2 interconnection using VRF leaking

Layer 2 interconnection using VRF leaking in an EVPN network provides these features:

  • Enables controlled Layer 2 communication between different VRF instances by selectively sharing routes.

  • Maintains VRF isolation and segmentation while allowing traffic interconnection through EVPN Route type 2 (MAC+IP) import.

  • Permits interconnection of VRFs at Layer 2 using gateways or bridges that forward traffic between VRFs.

  • Allows definition of traffic policies to control flow, including filtering based on EVPN EVI and MAC addresses.

  • Forwards Layer 2 frames between VRFs while preserving Layer 3 isolation.


Configure VRF leaking for EVPN E-LAN

This procedure enables controlled route leaking between the global routing table and a VRF routing table within an EVPN E-LAN environment. VRF leaking allows selective sharing of routes between VRFs and the global routing table, facilitating communication across different routing domains while maintaining segmentation and policy control. This is essential in multi-tenant or segmented network architectures where certain routes need to be shared securely and efficiently.

Procedure

  1. Configure BGP where the router performs the route leak.

    Example:

    Router(config)# router bgp 100
    Router(config-bgp)# bgp router-id 10.10.10.10
    Router(config-bgp)# address-family ipv4 unicast
    Router(config-bgp-af)# network 172.16.20.0/24
    Router(config-bgp-af)# exit
    Router(config-bgp)# address-family vpnv4 unicast
    Router(config-bgp-af)# exit
    Router(config-bgp)# vrf ORANGE
    Router(config-bgp-vrf)# rd 100:100
    Router(config-bgp-vrf)# address-family ipv4 unicast
    Router(config-bgp-vrf-af)# network 192.168.10.0/24
    Router(config-bgp-vrf-af)# commit
  2. Configure the route policies.

    These policies help you filter which prefixes are permitted to be leaked. In this example, the route-policy GLOBAL-2-VRF and route-policy VRF-2-GLOBAL are used.

    Example:

    Router(config)# route-policy GLOBAL-2-VRF
    Router(config-rpl)# if destination in (172.16.20.0/24) then
    Router(config-rpl-if)# pass
    Router(config-rpl-if)# endif
    Router(config-rpl)# end-policy
    Router(config)# route-policy VRF-2-GLOBAL
    Router(config-rpl)# if destination in (192.168.10.0/24 le 32) then
    Router(config-rpl-if)# pass
    Router(config-rpl-if)# endif
    Router(config-rpl)# end-policy
  3. Configure the VRF and apply the route-policy.

    Example:

    
    Router(config)# vrf ORANGE
    Router(config-vrf)# address-family ipv4 unicast
    Router(config-vrf-af)# import from default-vrf route-policy GLOBAL-2-VRF
    Router(config-vrf-af)# import route-target
    Router(config-vrf-import-rt)# 100:100
    Router(config-vrf-import-rt)# exit
    Router(config-vrf-af)# export to default-vrf route-policy VRF-2-GLOBAL
    Router(config-vrf-af)# export route-target
    Router(config-vrf-export-rt)# 100:100
    Router(config-vrf-export-rt)# commit
  4. Running configuration of VRF leaking.

    Example:

    
    router bgp 100
     bgp router-id 10.10.10.10
     address-family ipv4 unicast
      network 172.16.20.0/24
     !
     address-family vpnv4 unicast
     !
     vrf ORANGE
      rd 100:100
      address-family ipv4 unicast
       network 192.168.10.0/24
      !
     !
    !
    route-policy GLOBAL-2-VRF
      if destination in (172.16.20.0/24) then
        pass
      endif
    end-policy
    !
    route-policy VRF-2-GLOBAL
      if destination in (192.168.10.0/24 le 32) then
        pass
      endif
    end-policy
    !
    vrf ORANGE
     address-family ipv4 unicast
      import from default-vrf route-policy GLOBAL-2-VRF
      import route-target
       100:100
      !
      export to default-vrf route-policy VRF-2-GLOBAL
      export route-target
       100:100
      !
     !
    !
  5. Use the show route command to verify the prefixes appear in the RIB and BGP tables.

    Example:

    Router# show route
    Codes: C - connected, S - static, R - RIP, B - BGP, (>) - Diversion path
           D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
           N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
           E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
           i - ISIS, L1 - IS-IS level-1, L2 - IS-IS level-2
           ia - IS-IS inter area, su - IS-IS summary null, * - candidate default
           U - per-user static route, o - ODR, L - local, G  - DAGR, l - LISP
           A - access/subscriber, a - Application route
           M - mobile route, r - RPL, t - Traffic Engineering, (!) - FRR Backup path
    
    Gateway of last resort is not set
    
    C    10.88.174.0/24 is directly connected, 1d20h, MgmtEth0/RSP0/CPU0/0
    L    10.88.174.223/32 is directly connected, 1d20h, MgmtEth0/RSP0/CPU0/0
    L    10.10.10.10/32 is directly connected, 04:33:44, Loopback100
    C    172.16.20.0/24 is directly connected, 07:03:18, HundredGigE0/0/0/24
    L    172.16.20.1/32 is directly connected, 07:03:18, HundredGigE0/0/0/24
    B    192.168.10.0/24 is directly connected, 03:02:21, HundredGigE0/0/0/0 (nexthop in vrf ORANGE)
    
    Router# show ip bgp
    BGP router identifier 10.10.10.10, local AS number 100
    BGP generic scan interval 60 secs
    Non-stop routing is enabled
    BGP table state: Active
    Table ID: 0xe0000000   RD version: 5
    BGP main routing table version 5
    BGP NSR Initial initsync version 3 (Reached)
    BGP NSR/ISSU Sync-Group versions 0/0
    BGP scan interval 60 secs
    
    Status codes: s suppressed, d damped, h history, * valid, > best
                  i - internal, r RIB-failure, S stale, N Nexthop-discard
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network            Next Hop            Metric LocPrf Weight Path
    *> 172.16.20.0/24     0.0.0.0                  0         32768 i
    *> 192.168.10.0/24    0.0.0.0                  0         32768 i
    
    Processed 2 prefixes, 2 paths

    This show output displays the information for the VRF ORANGE:

    Router# show route vrf ORANGE 
    Codes: C - connected, S - static, R - RIP, B - BGP, (>) - Diversion path
           D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
           N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
           E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
           i - ISIS, L1 - IS-IS level-1, L2 - IS-IS level-2
           ia - IS-IS inter area, su - IS-IS summary null, * - candidate default
           U - per-user static route, o - ODR, L - local, G  - DAGR, l - LISP
           A - access/subscriber, a - Application route
           M - mobile route, r - RPL, t - Traffic Engineering, (!) - FRR Backup path
    
    Gateway of last resort is not set
    
    B    172.16.20.0/24 is directly connected, 01:43:49, HundredGigE0/0/0/24 (nexthop in vrf default)
       C    192.168.10.0/24 is directly connected, 07:06:38, HundredGigE0/0/0/24
       L    192.168.10.2/32 is directly connected, 07:06:38, HundredGigE0/0/0/0
    
    
    Router# show bgp vrf ORANGE
    BGP VRF ORANGE, state: Active
    BGP Route Distinguisher: 100:100
    VRF ID: 0x60000003
    BGP router identifier 10.10.10.10, local AS number 100
    Non-stop routing is enabled
    BGP table state: Active
    Table ID: 0xe0000012   RD version: 9
    BGP main routing table version 9
    BGP NSR Initial initsync version 4 (Reached)
    BGP NSR/ISSU Sync-Group versions 0/0
    
    Status codes: s suppressed, d damped, h history, * valid, > best
                  i - internal, r RIB-failure, S stale, N Nexthop-discard
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network            Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 100:100 (default for vrf ORANGE)
    *> 172.16.20.0/24     0.0.0.0                  0         32768 i
    *> 192.168.10.0/24    0.0.0.0                  0         32768 i
    
    Processed 2 prefixes, 2 paths